My fan has gone nuts...

[CLAYTON]

When I turn the fan on for heat or air on anything above half way makes it sound like a deep hum/vibration. It'll do it on 3/4 and all the way up but not on the lower two levels. The sound and hum will increase on the highest level. The fan will still blow air on all levels. I don't have dual climate. Any ideas what this might be.

 

[Alan Reagan]

When mine did it, some pine straw had made it's way down into the fan.



It was on my '01. There are three screws that hold the fan in place. The one against the firewall was put in by the devil himself.



I dropped the fan, cleaned out the plenum and the problem was solved.

 

[MMeier]

Sounds like some debris has made it way into the fan housing!

 

[CLAYTON]

I think that I must have one of those self fixing trucks. Got back in my truck and turned up the air to see where the noise is coming from and it stopped doing it I think that maybe something got sucked in the intake part of the system. Is the intake right behind the glove box? How do you get back in there to clean it out? Any body know? Thanks for the help!!

 

[SThorud]

When you drop the fan you can see up to the inlet cowl. It's a wide-open straight shot from there to the squirrel cage.



The HVAC systems are built up as a unit and bolted to the firewall during assembly. The engineer just never bothered to realize that the screw up next to the firewall for the fan is near impossible to remove without removing the HVAC unit from the firewall.

 

[DGFoster]

Mine did that,had a bunch of leaves and pine needles,cleaned it out and all is well.